A little broadcast workflow

Published February 20, 2013

Last weekend we had a pretty big concert here, which was not the usual “another average day in the office” type, we needed to record 96 channels to multiple rigs, making backups and mixing stereo live broadcast sound as well as feed what we call “narrow pgm” for the cameramen and for the projectionist.

Why is it a big deal?

Well, it’s not such a big deal, but when your gig is full of stars, you need to record and mix for broadcast and dvd, there are many things that can go wrong so meticulous planning is necessary.

The band: drum kit, 2 percussion sets, 4 strings, 4 brass, 6 keyboards, 2 guitars, 1 bass, 4 vocalists. Because of the many in-ear monitors (22 stereo) we planted many ambience mics so the performers could hear what’s going on in the hall, and obviously it was necessary because of the recording too.

The system

When you have TV, recording, live mix, broadcast mix, different additional feeds, the system needs to be failsafe. So, we planned this system for the day.

FOH position, one Avid Venue console connected to a Pro Tools HD system recording 96 tracks at 24 bit 48kHz, split from stage using an analogue snake. In the broadcast studio we receive 2 madi opticals from the monitor position, that two madi were split at the studio so the Studer Vista 8 has all 96 inputs and a Nuendo records 96 tracks, and a Pyramix DAW records the 96 tracks running as a backup.

Fortunately we had a few days rehearsal so we could test parts of the system. We had no chance to test the whole planned rig, but it was sufficient for us. During this test process it came to light that the very expensive Digico SD7 monitor console is completely unable to accept any external clock which is a surprise for me and frankly at this price point this is quite unacceptable, but 2 days before the show we could not “throw out” the console. Instead, we reversed the clock order as the Digico became the clock master. At this point everyone was concerned about the Digico’s ability to keep up with being the clock master so we tested a few clocking device and found that the Studer’s own device is quite stable even if it’s receiving a somewhat wobbly clock.

Be failsafe

The idea was that if everything fails do to some severe clocking issue or because of anything else, the Pro Tools will still record everything as it is fed from analogue lines. Our plan included other redundancy too. As I mentioned earlier we split the madi signal from the monitor, so we had separate madi for our Steadier and separate for our Pyramix. So if the Pyramix fails, everything goes on we only loose one backup. If the Steadier fails (highly unlikely but who knows) we still have the Pyramix running and after a restart the Nuendo and the Steadier can join anytime. If Pro Tools fails, then we have the Nuendo and the Pyramix running. I made a little picture to make this clear:

We even tested different “worst case scenario” situations where we deliberately removed the sync, then reconnected it, removed one madi stream, etc. In most cases we lost a few seconds of audio on one recorder, but because of the independent feeds we always had some perfect lines.

But, you can never have enough, so and additional Pro Tools HD was recording our PGM (mixed stereo programme output) separately just in case.

Results

Fortunately each and every recorder was rock solid during the show, so now we have many hundreds of gigabytes backup, which we are obviously happily store as long as we need to.

I know that we could have a much simpler system to record the show, but the multiple independent backup solution seems to be the most failsafe solution for this kind of bigger events. My dream would be to use multiple Pro Tools rigs so even the session files would be compatible with each other, but as now we have a bunch of broadcast wave files, this is not a serious problem, but only a personal wish.